Red Watermilfoil

Species: Myriophyllum verrucosum

weed identification

common name
Red Watermilfoil

Red watermilfoil is a native submerged plant with stems that grow up to 4 metres in length. Its leaves form whorls along the length of its stems. The plant produces female and male (yellow) flowers year round. The red watermilfoil can range from green to reddish purple in colour. The plant often flowers on drying mud at the edge of the water body. This is a widespread and common plant that does not die back during winter.


Commonly found in fresh or slightly saline water bodies at the water’s margin.

native or exotic?

The red watermilfoil reproduces by stem fragments and seeds.


Seeds and fragments are transported by flooding and animals.


Red watermilfoil is known to be a food source for some waterbirds and stock as well as being effective at absorbing nutrients from a water body.

What does Red Watermilfoil look like?

Use these images below to help you decide whether you are dealing with Red Watermilfoil.

Disadvantages of Red Watermilfoil

The red watermilfoil can become abundant under high nutrient conditions which can negatively impact a water body:

  • Can produce an unpleasant odour

  • Potential to obstruct water flow, block pumps

  • May dominant water body, inhibiting growth of other aquatic plants
  • Reduce food and habitat for fish

  • Restricts water-based recreation


AQ200 Aquatic Herbicide – Chemical Herbicide designed to kill submerged weeds quickly. Use on mild to severe infestations.

Aquatic Weed Rake and Razor combo – DIY physical removal. Ideal for mild infestations, sensitive water bodies or to aid herbicide treatment

Aquatic Harvesting (Mobitrac) – Large amphibious machine that clears submerged aquatic weeds. Book this service for severe infestations or for larger water bodies.

prevention options

Aquatic Blue – Blue dye that may reduce temperature of the water body by reducing UV light penetration. This may then increase oxygen saturation.

Aerating Fountains – Reduces the severity and likelihood of aquatic weed infestations. Use in any body of water.